The present position of surgery of the NERVOUS SYSTEM

The developments of neurological surgery during recent years have been so rapid and so important that every Practitioner ought to make himself acquainted with them, ln order that he may form his own opinion as to their value and be able to offer to his patients such advantages as are to be derived from them. Successful intervention in disease of the nervous system Spends upon accurate diagnosis almost more than in any ?ther region of the body. One may embark upon an abdominal operation with the intention of performing a gastroenterostomy, and end by removing a gall-stone ; ^e failure to make a correct diagnosis beforehand, although lettable, has done no harm. But with an intracranial

The developments of neurological surgery during recent years have been so rapid and so important that every Practitioner ought to make himself acquainted with them, ln order that he may form his own opinion as to their value and be able to offer to his patients such advantages as are to be derived from them. Successful intervention in disease of the nervous system Spends upon accurate diagnosis almost more than in any ?ther region of the body. One may embark upon an abdominal operation with the intention of performing a gastroenterostomy, and end by removing a gall-stone ; ^e failure to make a correct diagnosis beforehand, although lettable, has done no harm. But with an intracranial 1 A Paper read at a Meeting of the Biistol Medicc-Chirurgical Society ?n Wednesday, February nth, 1925. operation the conditions are entirely different ; an exploration of the frontal region when the tumour lies in the cerebellar fossa would not only fail to relieve the patient, but would inevitably leave him worse off than he was before.
Recognising this, it seems to me that the surgeon must always lean heavily upon the support of the neurologist-Harvey Cushing, who occupies so prominent a position m the field of neurological surgery, has envisaged a superman so versed in all the clinical and laboratory knowledge neurology that he can make his own diagnosis, and so skilled in the practical side of surgery that he can perform his own operations. I cannot think this to be anything but a-Utopian dream, although we in this country have had m Victor Horsley one who must have come within measurable distance of such an ideal. But a Victor Horsley is born, not made.
It is manifestly impossible for me to do more than indicate briefly what Surgery has to offer in the treatment of some of the diseases of the central nervous system-^ have selected four groups of cases which have so far yielded results which can scarcely be ignored even by tne most conservative of physicians, namely pituitary tumours* cerebello-pontine tumours, meningeal endotheliomata, and spinal tumours. i.

Pituitary Tumours.
There are few things more striking in the whole range of modern physiology and medicine than the advances which in recent years have been made in the pathology of the i Vl6 ductless glands. For many years the thyroid was only organ of internal secretion of which we had any iea^ knowledge ; now the subject of endocrinology has attained stupendous proportions ; it is discussed in the public Press* novelists and playwrights make capital out of it, whilst laymen converse freely of the testicle, politely termed donkey-gland, even at meal-times. Whether the pituitary will, like the thyroid, ever be successfully attacked on account of disordered function alone I cannot say. At present its surgical interest lies solely in the symptoms of Pressure which are caused by enlargement of the gland or by tumours in its vicinity. The chief of these symptoms are failure of vision and intolerable headache for which relief can be obtained only by operative means, and as far as our present knowledge goes these are the only symptoms f?r which operation is justifiable.
The tumours which cause these symptoms fall into two main groups, those which arise within the gland and those which originate in its immediate neighbourhood. The former are almost entirely simple adenomatous tumours the pars anterior ; they excavate the sella turcica so as to ^e easily recognisable by X-ray examination ; as they invade cranial cavity, still encapsuled by a dural envelope, tlley push upwards the optic chiasma and stretch the optic nerves. Characteristic defects of the visual fields appear, and severe tension headaches occur. Generally speaking, ^le glandular symptoms in these cases are those of deficient Secretion or hypopituitarism, namely hebetude, obesity, airlessness, sexual impotence, increased sugar tolerance, o\v blood pressure and subnormal temperature. It is a Matter of considerable importance to recognise the fact that Sllch patients bear operations badly, and have a remarkably ?w resistance^ to microbic attack, so that the glandular syrnptoms have to be taken into account when an operation ls c?ntemplated.
In the second or suprapituitary group we usually find ?ne of two kinds of tumour, the one a meningeal tumour in tlle interpeduncular space, and the other a tumour or cyst of complex histological structure, probably arising in the ?L-XLli. No. 156. infundibulum. These lie above the chiasma and compress it from above downwards (Fig. i).
Pituitary tumours may be approached either (i) by a temporal operation with elevation of the frontal and temporal lobes, as was practised by Horsley more than twenty years ago ; (2) from below through the sphenoidal sinus on the lineS advocated by Gushing; or (3) by turning down a fronts osteoplastic flap hinged in the temporal fossa, and elevati^ the frontal lobe, as was originally planned by Fi^e (Figs. 2 and 3). The last is the method which I am ll0V using, as giving the cleanest and freest exposure cf lesion, and as being applicable to the suprapituitary well as to the intrapituitary tumour.   Outlines of osteoplastic flap for frontal approach (modified Frazier operation).   Journal of Surgery.?Vol, XI., No. 43, 1924. allows of the rejection of advanced and unsuitable cases. ?an be shelled out with ease, but in doing so the medulla, Pr?bably through its blood supply, is so damaged that the C?mmon result is death from respiratory failure. I have not removed one of these tumours completely since 1921. Up to that time I had so operated upon nine patients, of whom eight died, whilst the only survivor made a complete and excellent recovery and remains well five years later. There is, however, another way of dealing with these tumours, which gives very satisfactory results, and which I have practised for some years, namely the removal of the growth piecemeal from within its capsule. The tumour having been exposed, the capsule is incised, the mass is gradually broken up with a curette, and the fragments are removed by mean^ of a suction apparatus. I have now done 19 such operation^ with 3 deaths, a mortality of 16 per cent., which is in striking contrast with the 88 per cent, mortality of the operation by total removal. A further series of 12 cases have been treated by decompression alone, and although one of the patients lived for eighteen years in complete comfort, and then died of an independent malady, these patients have not, generally speaking, been benefited to anything like the same extent as those treated by partial removal, whilst the mortality of the decompression operation was 40 per cent, as compare<^ with the 15 per cent, of intracapsular or partial remova ?
This difference may be accounted for partly by the fact that most of the cases for which only decompression was done ^ere amongst my earlier operations, and partly because in many of them the intracranial pressure was so far advanced tha the tumour could not be exposed.
thef In these extra-cerebellar cases, then, we have ano definite group of intracranial tumours for which surged nly offers an increasingly bright outlook. The results can ? ^ be improved by earlier diagnosis, which will enable ^ tumour to be attacked whilst it is still small, and befoie ?ft the intracranial pressure has been raised, before, in lac , classical symptoms of intracranial tumour have appeal Of those patients still alive and well two were operated upon 16 years ago, three 10 years ago, and the rest between 3 and 6 years ago. The longest survival after decompression alone was 16 months.
As these meningeal tumours can often be diagnosed and localised with reasonable certainty, and before signs of increased intracranial pressure appear, they can be removed through an osteoplastic opening. This is a great advantage, as it avoids the very considerable inconvenience of a large cranial defect.
Seven of the above-mentioned patients who recovered were operated upon in that manner and consequently have no cranial defect.
L nfortunately, such tumours form only a small proportion of the whole, for of 200 tumours of the forebrain (frontal, temporal, occipital, and parietal) upon which I haVe operated, no fewer than 160 (80 per cent.) were of infiltrating or malignant character, the great majority being gliomata. The cerebellar tumours, of which there are 60 instances in my series, are almost exclusively gliomata 01 gliomatous cysts. It must not be supposed, however, that all these cases of glioma are hopeless and that nothing can be done for them. On the contrary, the results of decompression and of partial removal compare very favourably with the result5 of many merely palliative operations elsewhere, as f?r example colostomy for cancer of the colon. Lately we have been burying radium (50 or 100 milligrams for 24 houi?) in gliomata with surprising results. The gliomata appeaf' so far as our observations at present go, to be peculin1^ vulnerable to radium.
In operations for tumour of the brain the most import^11 factor upon which hinges success or failure is the degree ? intracranial pressure. In the presence of a high degree 0 pressure the simplest tumour removal is a formidable nnd dangerous task. In many cases, of course, it is impossi^e to make a diagnosis of tumour until papilledema appears, but that and the other signs of increased intracranial pressure should not be allowed to advance far before ?Peration is undertaken. The classical symptoms of cerebral humour should be regarded rather as danger signals, or, if far advanced, as signs of impending death. We no longer vvait for signs of general peritonitis before operating for appendicitis ; neither should we postpone operation for cerebral tumour until headache, vomiting and papilledema are present. We must look for better results not only to the surgeon from improvements of technique, but also and chiefly to the physician from earlier and more accurate diagnosis, as well as in a greater readiness to procure for his Patient the only treatment which offers any hope. We are Uot looking to him in vain. I have had the privilege of forking with many physicians, and I have been greatly lrnpressed with the enormous improvement in accuracy localisation which has been evident during the past few years.
It may be that we shall be able to derive some additional distance in the future by radiological methods, and on ^us point I should like to make a few observations. Ventriculography has now had a fair trial at the hands ?* several workers, notably Jefferson of Manchester. The Procedure is to inject air into the lateral ventricle of the brain, and to take radiograms with the head in various Positions so as to ascertain whether one or other ventricle ls obliterated, dilated, or otherwise deformed. It has been Maimed that tumours, unlocalisable by other means, can be Seated, and doubtless in some obscure cases this method d?es afford assistance. As, however, the percentage of cases in which neurological examination fails to localise a tumour is very small, and as the operation is by no means free from danger, its sphere of usefulness is necessarily limited.
It has not anything like the same value for the brain as Sicard's radiographic method has for the spine.
The fourth group of cases, namely that of spinal tumours, provides some of the most gratifying of all the results of operation upon the central nervous system.
In looking through, as I did recently, many volumes the Transactions of this Society, I was most interested to find in the very firsts-number (1883) the report of a case of Spinal Tumour by Dr. Long Fox, illustrated by an excellent full-page drawing. It is labelled " sarcoma," but it  doubtless what we to-day know as an endothelioma.
The drawing differs in no essential respect from the typical picture ^vhich I show here (Fig. 4) These tumours are capable^of diagnosis at an early stage by neurological signs, by the condition of the cerebrospinal fluid, and by radiography, and there is no excuse for blowing a patient to become totally paralysed and finally to succumb when operation offers the opportunity of a c?mplete and permanent cure. The radiographic method ?* diagnosis, originated by Sicard of Paris, depends upon the arrest, at the point of blockage, in the spinal canal, of a substance opaque to the X-rays. Such a substance is lipiodol, a heavy inert oil containing iodine, and it is remarkably opaque to the X-rays, more so, in fact, than bone.
When it is desired to ascertain the presence or absence, or the level, of a block in the spinal canal, a cubic centimetre of this lipiodol is injected into the cisterna magna through a sub-occipital puncture, the patient being in a sitting position, and radiograms of the spine are taken. If no obstruction exists the lipiodol falls rapidly to the bottom of the theca, and appears opposite the second sacral vertebra as a rounded or conical shadow. If, however, a tumour, abscess, or other block is present, then the lipiodol is shown arrested at the upper level of the obstruction (Fig. 5). This method affords a valuable means of diagnosis in cases of spin^ tumour, for it not only shows the presence of a block i11 the spinal cord, but also demonstrates the exact level of  "the obstruction with relation to the bones, and enables the surgeon to plan his laminectomy with the greatest accuracy ( Fig. 6). It is only the upper level, however, which is thus demonstrated. If it is desired to show the lower level of "the tumour, or in other words to estimate its longitudinal extent, a thing which neurological examination does not enable us to do, then the lipiodol injection is made by lllmbar puncture, and the radiograms taken with the patient 111 the head down position.
As we become more familiar with the interpretation of ^Piodol-radiograms, we shall doubtless be able to derive formation regarding other spinal lesions such as chronic Meningitis and meningitis circumscripta. It has already Proved of great value in traumatic cases when the question laminectomy has to be decided.